An observation of Theremin Purity based upon Clara Rockmore's theremin as the standard.

1. You must have a [i]"Heterodyne Voice"[/i] as Lev discovered while moving about the oscillators in his test equipment. If he had not heard this [i]"oscillator whistle"[/i] which is the [b]impetus[/b] to his invention there would be no theremin.

2. Pitch/Volume controlled with non-physical contact while playing musical sound.

3. The instrument should only connect to an amplifier and external ground & power.

Violating one of these three basic theremin principles, which are in the order of what, I consider important, would transform a theremin into a Hybrid of Clara's original purity but still be a theremin.

Some Theremin [b]Impurities[/b]: Not using an analog heterodyne voice, using digital reverb or digital sound storage. Having physical contact with the instrument while playing, like using earphones/headphones and effects pedals, which would contaminate the non-contact purity.

The theremin is a "sound" in everyone's ears that is magical, a surreal whisper from the ether, even angelic for those that were invited.

[i]"Maybe there a three groups of theremin, Pure - Hybrid - In Spirit"

>An observation of Theremin Purity based upon> Clara Rockmore's theremin as the standard.

Clara established high standards for the Theremin’s playability and tone. She also established high standards for performing on the Theremin. I view Clara and Lev as giants upon who’s shoulders others can stand. They set high standards.

Clara and Lev were pioneers. I doubt if Clara and Lev’s contributions are the last that will be made to the world of space-controlled music-making, though.

> 1. You must have a "Heterodyne Voice" as Lev> discovered while moving about the oscillators> in his test equipment. If he had not heard> this "oscillator whistle" which is the impetus> to his invention there would be no theremin.

Agreed. The interaction between the reference and sensing oscillators modulates the shape of the resultant waveform. Particularly in the lower range where the reference and sense oscillators are on the verge of coupling where the sine wave is greatly distorted. While the frequency of the sensing oscillator will change pretty much instantaneously with the movement of the hand, the change in the waveshape would likely lag a bit. My theory is that when first hitting a note (jump to it from another pitch) the waveshape is closest to a sine and then distorts as the oscillators try to pull (couple) each other. This may explain the magical quality of “the clam” that Clara uses.

The oscillators in Clara’s Theremin were tuned at relatively low frequencies (longer wavelengths) that may be more subject to the coupling effect.

Absolutely! Space-control is a medium unto itself. Other instruments are blown, bowed, struck – whatever and each have their unique sound. For example, one can bow a xylophone and get a cool sound – however, it no longer sounds like a xylophone! When one touches the theremin it may create unique, wonderful, and musical sounds – however it will not sound space-controlled anymore.

> 3. The instrument should only connect to an> amplifier and external ground & power.

Grrrr :) Please forgive me for using my CV outputs – though I have only recorded one work wherein I used the CV out to control my analog synth (the middle section of the October contest piece: “Take me out to the Ballgame” wherein I control my Aries Modular from the Epro’s CV output – the actual sound is a “tuned air” whistle. To add to the impurity, in the same passage I created vocal humming by running my Theremax thru a Harmonizer).

In fact, the input stage of just about any sound processor will be an amplifier – after all, you didn’t say that the amplifier had to connect to a speaker!

(*** Evile grin!! ***)

> Violating one of these three basic theremin> principles, which are in the order of what, I> consider important, would transform a theremin> into a Hybrid of Clara's original purity but> still be a theremin.>> Some Theremin Impurities: >> Not using an analog heterodyne voice

(discussed already)

> using digital reverb or digital sound storage.

Does this mean that vinyl is the only appropriate medium? To press a recording on vinyl requires A LOT of external processing. From the master tape to the vinyl is a trip through equalizers, compressors, and the riaa rolloff in order to cut grooves that aren’t overly deep and wide – then the recording is heard via a phonograph needle, a ceramic or magnetic pickup, and a phono preamp that reverses the riaa rolloff done when the record was pressed. I can’t understand how such a system is more pure than a digital recording?

I base my research on the idea that the “theremin hybrid” will bring forth-new ideas that can only be dreamed at the moment. There are so few pioneers, people who hear the theremin and technically search for more… In the hybrid we can counterfeit the voice or falsify the control but what really matters is arriving at music, something inordinately beautiful that people will hear and say, “that’s a theremin”.